Cargando…
Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2
We have recently cloned a novel splice variant of cyclin D2 termed as cycD2SV. CycD2SV overexpression in several immortalized cell lines led to formation of ubiquitinated protein aggregates accompanied by a significant decrease in cell proliferation. Based on immuno co-localization and ultrastructur...
Autores principales: | , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2013
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3542336/ https://www.ncbi.nlm.nih.gov/pubmed/23326442 http://dx.doi.org/10.1371/journal.pone.0053503 |
_version_ | 1782255497765715968 |
---|---|
author | Wafa, Karim MacLean, Jessica Zhang, Feixiong Pasumarthi, Kishore B. S. |
author_facet | Wafa, Karim MacLean, Jessica Zhang, Feixiong Pasumarthi, Kishore B. S. |
author_sort | Wafa, Karim |
collection | PubMed |
description | We have recently cloned a novel splice variant of cyclin D2 termed as cycD2SV. CycD2SV overexpression in several immortalized cell lines led to formation of ubiquitinated protein aggregates accompanied by a significant decrease in cell proliferation. Based on immuno co-localization and ultrastructural analysis experiments, cycD2SV protein aggregates were frequently found in various subcellular compartments such as endosomes, autophagosomes, lysosomes and the microtubule organizing centre. Secondary structure analysis revealed that the amino terminal α-helix in cycD2SV is not tightly packed with the cyclin box suggesting a misfolded conformation compared to other cyclins. Deletion analysis suggests that 1–53 amino acid region of cycD2SV may be required for protein aggregation and 54–136 amino acid region may mediate cell cycle inhibition. Based on co-immunoprecipitation experiments, we have shown that cycD2SV binds to cycD2 as well as CDK4. In addition, gene expression analysis demonstrated an upregulation in GADD45α and dynamin 2 mRNA levels in cycD2SV overexpressing cells. These two proteins are known to play critical roles in the DNA damage response and apoptosis pathways. TUNEL experiments were negative for apoptosis, however, cycD2SV expressing cells were more sensitive to cell death induced by external stressors such as trypsinization. Collectively our results suggest that cycD2SV mediates cell cycle inhibition by sequestering endogenous cell cycle proteins, such as cycD2 and CDK4, and possibly targeting them for ubiquitin mediated protein degradation. |
format | Online Article Text |
id | pubmed-3542336 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-35423362013-01-16 Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 Wafa, Karim MacLean, Jessica Zhang, Feixiong Pasumarthi, Kishore B. S. PLoS One Research Article We have recently cloned a novel splice variant of cyclin D2 termed as cycD2SV. CycD2SV overexpression in several immortalized cell lines led to formation of ubiquitinated protein aggregates accompanied by a significant decrease in cell proliferation. Based on immuno co-localization and ultrastructural analysis experiments, cycD2SV protein aggregates were frequently found in various subcellular compartments such as endosomes, autophagosomes, lysosomes and the microtubule organizing centre. Secondary structure analysis revealed that the amino terminal α-helix in cycD2SV is not tightly packed with the cyclin box suggesting a misfolded conformation compared to other cyclins. Deletion analysis suggests that 1–53 amino acid region of cycD2SV may be required for protein aggregation and 54–136 amino acid region may mediate cell cycle inhibition. Based on co-immunoprecipitation experiments, we have shown that cycD2SV binds to cycD2 as well as CDK4. In addition, gene expression analysis demonstrated an upregulation in GADD45α and dynamin 2 mRNA levels in cycD2SV overexpressing cells. These two proteins are known to play critical roles in the DNA damage response and apoptosis pathways. TUNEL experiments were negative for apoptosis, however, cycD2SV expressing cells were more sensitive to cell death induced by external stressors such as trypsinization. Collectively our results suggest that cycD2SV mediates cell cycle inhibition by sequestering endogenous cell cycle proteins, such as cycD2 and CDK4, and possibly targeting them for ubiquitin mediated protein degradation. Public Library of Science 2013-01-10 /pmc/articles/PMC3542336/ /pubmed/23326442 http://dx.doi.org/10.1371/journal.pone.0053503 Text en © 2013 Wafa et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Wafa, Karim MacLean, Jessica Zhang, Feixiong Pasumarthi, Kishore B. S. Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title | Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title_full | Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title_fullStr | Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title_full_unstemmed | Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title_short | Characterization of Growth Suppressive Functions of a Splice Variant of Cyclin D2 |
title_sort | characterization of growth suppressive functions of a splice variant of cyclin d2 |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3542336/ https://www.ncbi.nlm.nih.gov/pubmed/23326442 http://dx.doi.org/10.1371/journal.pone.0053503 |
work_keys_str_mv | AT wafakarim characterizationofgrowthsuppressivefunctionsofasplicevariantofcyclind2 AT macleanjessica characterizationofgrowthsuppressivefunctionsofasplicevariantofcyclind2 AT zhangfeixiong characterizationofgrowthsuppressivefunctionsofasplicevariantofcyclind2 AT pasumarthikishorebs characterizationofgrowthsuppressivefunctionsofasplicevariantofcyclind2 |